Clamping device for battery cells as well as battery module, battery, battery system, vehicle and method for producing a battery module

ABSTRACT

The present invention relates to a clamping device ( 300 ) for battery cells ( 100 ), characterized by: a container that comprises a space ( 310 ) with a variable volume for receiving a fluid, the container being designed such that a battery cell ( 100 ) or a plurality of battery cells ( 100 ) can be clamped. The invention also relates to a battery module, a battery, a battery system, a vehicle and a method for producing a battery module ( 20; 30; 40; 50; 60 ).

BACKGROUND OF THE INVENTION

It is conceivable that greater use is being made of new battery systems(rechargeable battery systems), for example having lithium ionrechargeable batteries, lithium polymer rechargeable batteries or nickelmetal hybrid rechargeable batteries, both in the case of stationaryapplications, for example wind turbines, and also in the case of mobileapplications, for example in the case of electric vehicles (EV) orhybrid electrical vehicles (HEV) as rechargeable electrical energystorage devices (EES).

A battery system comprises a multiplicity of battery cells by way ofexample cylindrical or prismatic battery cells. As a result of theirinternal cell resistance and the electrochemical processes that aretaking place, the battery cells become warm during the charging anddischarging procedures. The battery cells can be connected in series inorder to increase the electrical voltage and/or said battery cells canbe connected in parallel in order to increase the maximum electricalcurrent. The battery cells can be combined to form battery modules orbattery units. When using said battery cells to drive vehicles, it ispossible by way of example to connect approx. 100 battery cells (as atraction battery) in series or in parallel with one another.

A lithium ion battery cell comprises a positive electrode (cathode) anda negative electrode (anode) that can store in a reversible manner(intercalation) lithium ions (Li+) during the charging procedure or candischarge (deintercalation) lithium ions (Li+) during the dischargingprocedure. As a consequence, a periodic volume change of the electrodesoccurs during the charging/discharging procedure and said change can bein the range of approx. 10% to approx. 30%. The volume change of theelectrodes causes mechanical work in the electrodes and battery cellsand this accelerates the aging process of the battery cells and thusshortens the serviceable life of the battery cells. Moreover, theelectrodes “swell up” over the serviceable life of the battery cells, asa result of which the volume of the electrodes and the battery cellscontinues to increase in size over the serviceable life. Whereascylindrical battery cells (round cells) are more or less stable owing totheir winding geometry. prismatic battery cells and pouch cells shouldbe stabilized from the outside by means of a force that counteracts theincrease in volume. The force can be produced by way of example by meansof clamping the battery cells in a pack frame of a battery module.

FIG. 1 illustrates a schematic view of a battery module 10 in accordancewith the prior art.

The battery module 10 comprises a multiplicity of prismatic batterycells 100 ₁ . . . 100 ₄, which are arranged adjacent to one another, anda pack frame, which comprises a first end plate 210 ₁, a second endplate 210 ₂, a first clamping band 220 ₁ and a second clamping band 220₂ and encompasses and clamps the multiplicity of prismatic battery cells100 ₁ . . . 100 ₄. The production process of the battery module 10 caninclude by way of example arranging the multiplicity of battery cells100 ₁ . . . 100 ₄ between the first end plate 210 ₁ and the second endplate 210 ₂, applying an external force to the end plates 210 ₁, 210 ₂,so as to join the multiplicity of battery cells 100 ₁ . . . 100 ₄ andfasten the clamping bands 220 ₁, 220 ₂ to the end plates 210 ₁, 210 ₂,by way of example by means of a multiplicity of weld connections 215 ₁₁. . . 215 ₂₂ so as to receive the force 920 ₁, 920 ₂, that counteractsthe force of the multiplicity of joined battery cells 100 ₁ . . . 100 ₄.

The document DE 10 2014 204 245 that had not yet been published on thedate of application of the present invention discloses an energy storageunit having a multiplicity of galvanic cells, wherein the cells in eachcase comprise outer contacts that are integrated in a cell housing(nutshell-cells) and the end plates comprise integrated contact platesor conductor plates.

In order to further increase the functionality and serviceable life ofbatteries (rechargeable batteries) and battery systems (rechargeablebattery systems) and to further simplify their production process, it ishowever necessary to provide an improved clamping device for the batterycells.

SUMMARY OF THE INVENTION

The inventive devices and method have the advantage that the batterycells can be clamped in a simpler manner. As a consequence, it ispossible to forego costly mechanical elements, constructions and/ormethod steps. Consequently, the number of components can be reduced andas a result the reliability increased. Furthermore, it is possible toreduce the volume and/or weight of the battery module or of the battery.Moreover, the structure of the battery module or module carrier can bemore freely designed, in other words by way of example simplified and/orwith a greater degree of integration. Moreover, the force for clampingthe battery cells can be applied in a simple, direct and flexiblemanner. Furthermore, the force can be applied in an elastic manner.Consequently, it is possible to compensate for the continuous swellingof the electrodes. As a consequence, it is possible to avoid the forceincreasing over the serviceable life of the battery cells. Consequently,it is possible to prevent or at least reduce loss of power and safetyrisks of the battery cells that can be caused by an increase in theforce.

In an expedient manner, the receptacle can comprise a membrane orflexible membrane. As a consequence, it is possible to avoid a relativemoment of two elements with respect to one another at a contact surface.Consequently, it is possible to simplify the structure of thereceptacle. Furthermore, it is possible to avoid leakage at the contactsurface. Moreover, it is possible to reduce the weight of thereceptacle.

In an expedient manner, the membrane can be embodied in a balloon-type,bag-type, cushion-type or drum-type manner. As a consequence, it ispossible to simplify the structure of the receptacle.

In an expedient manner, the membrane can be embodied in an elastic orflexible manner. As a consequence, the membrane can be used as an energystorage device or pressure storage device.

In an expedient manner, the membrane can comprise a foil/film, syntheticmaterial film, metallized film or metal foil or fabric. As aconsequence, the production process of the receptacle can be simplified.

In an expedient manner, the membrane can be embodied in an electricallyconductive manner. As a consequence, it is possible in particular in thecase of nutshell-cells to provide an electrical connection of thebattery cell or multiplicity of battery cells.

In an expedient manner, the membrane can comprise an electricallyconductive material, aluminum (Al), copper (Cu) or carbon (C). As aconsequence, it is possible to simplify the structure of the membrane.

In an expedient manner, the membrane can be embodied in an electricallynon-conductive manner. As a consequence, it is possible to reduce therisk of an electrical short circuit.

In an expedient manner, the receptacle can comprise an element forcarrying the membrane. As a consequence, it is possible to provide adead volume. Consequently, it is possible to influence the elasticconstant of the receptacle. Furthermore, the receptacle can providefurther functionalities.

In an expedient manner, the element can comprise a metal such asaluminum or a synthetic material. As a consequence, it is possible toimprove the compatibility of the material with the materials of thebattery module. Consequently, it is possible to reduce the risk ofcorrosion.

In an expedient manner, the element can be embodied as an end plate. Asa consequence, it is possible to reduce the number of components.

In an expedient manner, the receptacle can comprise a closure or a valvesuch as a safety valve or excess pressure valve. As a consequence, it ispossible to simplify the repair, maintenance and/or overhaul procedures.Furthermore, the safety aspect can be increased.

In an expedient manner, the receptacle can comprise a seam such as anadhesive seam or weld seam. As a consequence, it is possible to simplifythe production process of the receptacle.

In an expedient manner, the receptacle can contain the fluid. As aconsequence, it is possible to simplify the production process of thebattery module.

In an expedient manner, the fluid can be a liquid such as water (H₂O) orsilicone oil, gas such as an inert gas by way of example nitrogen (N₂)or a noble gas by way of example argon (Ar) or krypton (Kr), a gel or acompressible gel. As a consequence, it is possible to adjust the fluidto suit the requirements of the respective clamping device. Thereceptacle can contain multiple fluids.

In an expedient manner, the fluid can be compressible. As a consequence,it is possible to use the fluid as an energy storage device or pressurestorage device. As an alternative, the fluid can be non-compressible.

Furthermore, the invention provides a battery module that comprises theabove described clamping device.

Furthermore, the invention provides a battery that comprises the abovedescribed clamping device or the above described battery module.

Furthermore, the invention provides a battery system that comprises theabove described clamping device, the above described battery module orthe above described battery.

Furthermore, the invention provides a vehicle, in particular a motorvehicle such as an electric motor vehicle, a hybrid vehicle or electricmotorbike (electric bike, E-bike), electric bicycle (pedal electriccycle, pedelec), a sea vehicle such as an electric boat or submarine(U-boat), an aircraft or a spacecraft, which comprises the clampingdevice that is described above and is connected to the vehicle; thebattery module that is described above and is connected to the vehicle;the battery that is described above and is connected to the vehicle andcomprises the battery system that is described above and is connected tothe vehicle.

In an expedient manner, the procedure of clamping the clamping devicecan comprise filling the space with the fluid and/or closing thereceptacle. As a consequence, it is possible during the productionprocess of the battery module to adjust the filling procedure to suitthe requirements.

In an expedient manner, the method can include furthermore filling thespace with the fluid, closing the receptacle and cooling or liquefyingthe fluid, wherein the procedure of clamping the clamping deviceincludes warming the fluid or allowing the fluid to warm in thereceptacle. As a consequence, it is possible to close the receptacleduring the production process of the battery module. Consequently, it ispossible to simplify the production process.

In an expedient manner, the method can furthermore include checking apressure of the fluid in the receptacle and/or adjusting the pressure.As a consequence, it is possible to correct the pressure of the fluid byway of example within the scope of a repair, maintenance and/or overhaulprocedure. Furthermore, it is possible to adjust the pressure of thefluid by way of example within the scope of the operation.

Consequently, it is possible to reduce the weight and/or costs, by wayof example production costs relating to material costs and processingcosts relating to assembly costs.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features and advantages of the present invention will be evidentto the person skilled in the art with reference to the attached drawingsand from the description hereinunder of exemplary embodiments that arehowever not to be regarded as limiting the invention.

FIG. 1 illustrates a schematic view of a battery module 10 in accordancewith the prior art,

FIG. 2 illustrates a schematic plan view of a battery module 20 having aclamping device 300 ₁ in accordance with an embodiment of the invention,

FIG. 3 illustrates a schematic plan view of a battery module 30 having aclamping device 300 ₁ in accordance with another embodiment of theinvention,

FIG. 4 illustrates a schematic plan view of a battery module 40 having aclamping device 300 ₁ in accordance with a further embodiment of theinvention,

FIG. 5 illustrates a schematic plan view of another battery module 50having a clamping device 300 ₁ in accordance with a further embodimentof the invention,

FIG. 6 illustrates a schematic plan view of a battery module 60 havingtwo clamping devices 300 ₁, 300 ₂ in accordance with a furtherembodiment of the invention,

FIGS. 7-15 illustrate schematic lateral sectional views of clampingdevices 300 in accordance with embodiments of the invention,

FIGS. 16-18 illustrate schematic longitudinal sectional views ofclamping devices 300 in accordance with other embodiments of theinvention,

FIG. 19 illustrates a schematic sectional view of a clamping system 70in accordance with another embodiment of the invention, and

FIG. 20 illustrates a schematic sectional view of a modified clampingsystem 80 in accordance with this embodiment of the invention.

DETAILED DESCRIPTION

FIG. 2 illustrates a schematic plan view of a battery module 20 having aclamping device 300 ₁ in accordance with an embodiment of the invention.

The battery module 20 comprises a multiplicity of prismatic batterycells 100 ₁ . . . 100 ₄, which are arranged adjacent to one another, anda packaging device, by way of example a pack frame, which comprises afirst end plate 210 ₁, a second end plate 210 ₂, a first clamping band220 ₁ and a second clamping band 220 ₂ and encompasses the multiplicityof prismatic battery cells 100 ₁ . . . 100 ₄. The battery cells 100 ₁ .. . 100 ₄ can be embodied by way of example as nutshell-cells. Theclamping bands 220 ₁, 220 ₂ can be fastened to the end plates 210 ₁, 210₂ by way of example by means of a multiplicity of adhesive connections,riveted connections, weld connections 215 ₁₁ . . . 5 ₂₂ such as spotwelds or weld seams or screw connections.

Furthermore, the battery module 20 comprises a clamping device 300 ₁ forclamping the multiplicity of battery cells 100 ₁ . . . .100 ₄. Theclamping device 300 ₁ can be arranged, as illustrated by way of examplein FIG. 1, between the first end plate 210 ₁ and an adjacent batterycell 100 ₁ of the multiplicity of battery cells 100 ₁ . . . 100 ₄. Theclamping device 300 ₁ can where necessary be in a relaxed, by way ofexample folded, state. The clamping device 300 ₁ can be in a tensioned,by way of example unfolded, state so that it can clamp the multiplicityof battery cells 100 ₁ . . . 100 ₄. The clamping device 300 can beembodied as an expander clamping device (expander). The clamping device300 ₁ or the expander can comprise a flexible receptacle thatencompasses an internal space (hollow space) having a variable volume.The receptacle can comprise or be embodied as a membrane such as aflexible membrane. The membrane can be embodied by way of example in aballoon-type, bag-type, cushion-type or drum-type manner. The membranecan be embodied in an elastic or flexible manner. The receptacle or themembrane can comprise by way of example foils/films such as syntheticmaterial films, metallized films or metal foils or fabric. Thereceptacle or membrane can be embodied in an electrically conductivemanner so that the clamping device 300 ₁ can produce an electricalconnection. For this purpose, the receptacle or membrane can be coatedby way of example with an electrically conductive material such asaluminum, copper or carbon. Alternatively, the receptacle or membranecan be embodied in an electrically non-conductive manner. Furthermore,the clamping device 300 ₁ can comprise an element that supports themembrane.

The element can comprise by way of example a metal such as aluminum or asynthetic material. It is possible to connect one foil/film to anotherfoil/film or to the element by way of example by means of an adhesive,by way of example by means of a liquid adhesive material or an adhesiveband, or by means of welding such as laser welding, friction welding,ultrasound welding. The receptacle can be embodied in a cylindricalmanner. In the tensioned state, the clamping device 300 ₁ or thereceptacle contains a fill medium it its internal space. The fill mediumcan comprise a fluid, by way of example a liquid such as water orsilicone oil, a gas or inert gas such as nitrogen or a noble gas such asargon or krypton, or a gel such as a compressible gel. If the fillmedium is a gas, a gas having a low coefficient of diffusion can bepreferably used in order to prevent the leakage or slow down the rate ofleakage of the gas by way of example through the membrane.

The fill medium can be compressible or non-compressible. If the fillmedium is compressible, for example if a gas is used as the fill medium,the compressed fill medium can produce the force of clamping themultiplicity of battery cells 100 ₁ . . . 100 ₄. If the fill medium isnon-compressible, for example if a liquid is used as the fill medium,the force for clamping the multiplicity of battery cells 100 ₁ . . . 100₄ can be applied by means of a flexible membrane. Furthermore, theclamping device 300 ₁ or the receptacle can comprise a non-compressiblemedium such as water and a compressible medium such as air. The clampingdevice 300 ₁ or the receptacle comprises a closure. Consequently, theclamping device 300 ₁ or the receptacle can be closed or sealed afterbeing filled with the fill medium. Alternatively, the clamping device300 ₁ or the receptacle can comprise a valve such as a safety valve orexcess pressure valve. Consequently, the pressure of the fill medium canbe checked and/or adjusted by way of example within the scope of arepair, maintenance and/or overhaul procedure. If by way of example apart of the fill medium has escaped, a prevailing actual pressure can beincreased back to its desired pressure or, if the volume of themultiplicity of battery cells 100 ₁ . . . 100 ₄ is increased as a resultof the electrodes swelling, the actual pressure can be reduced back tothe desired pressure. In a similar manner, the actual pressure duringthe operation of the multiplicity of battery cells 100 ₁ . . . 100 ₄ canbe monitored and dynamically controlled. It is thus possible to increasethe actual pressure during the charging procedure if the volume of themultiplicity of battery cells 100 ₁ . . . 100 ₄ reduces, and during thedischarging procedure if the volume of the multiplicity of battery cells100 ₁ . . . 100 ₄ increases it is possible to reduce the actualpressure.

The production process of the battery module 20 can include arranging orpositioning the clamping device 300 ₁ and the multiplicity of batterycells 100 ₁ . . . 100 ₄ in the packaging device, in other words betweenthe first end plate 210 ₁ and the second end plate 210 ₂ and clamping orunfolding the clamping device 300 ₁ for clamping the multiplicity ofbattery cells 100 ₁ . . . 100 ₄. In so doing, the clamping or unfoldingprocedure can be performed by way of example by means of filling theclamping device 300 ₁ with the fill medium via a connection or aconnection aperture. When using a gas as the fill medium, the fillpressure can be by way of example 10 bar. The connection can bepermanently closed or sealed, by way of example adhered or welded, afterthe filling procedure. Alternatively, the connection can comprise aclosure or a valve such as a safety valve or an excess pressure valvethat remain in the connection after the filling procedure.Alternatively, said clamping device can be unfolded by way of example inaccordance with the thermal equation of state by (re-)heating a clampingdevice 300 ₁ to the ambient temperature, said clamping device alreadybeing filled with a gas and then rapidly cooled by way of example inliquid nitrogen.

FIG. 3 illustrates a schematic plan view of a battery module 30 having aclamping device 300 ₁ in accordance with another embodiment of theinvention.

The battery module 30 is similar to the battery module 20 that isdescribed with regard to FIG. 2, wherein the clamping device 300 ₁ isintegrated in the first end plate 210 ₁. In general, the clamping device300 ₁ can be integrated into a device of the packaging device.

FIG. 4 illustrates a schematic plan view of a battery module 40 having aclamping device 300 ₁ in accordance with a further embodiment of theinvention.

The battery module 40 corresponds essentially to the battery module 20that is described with regard to FIG. 2. In the case of the batterymodule 40, the clamping device 300 ₁, as illustrated by way of examplein FIG. 4, is arranged between two battery cells 100 ₂, 100 ₃ of themultiplicity of battery cells 100 ₁ . . . 100 ₄ so that the clampingdevice 300 ₁ is arranged essentially in the center of the battery module40. Consequently, the clamping device 300 ₁ can act in a symmetricalmanner on the multiplicity of battery cells. Furthermore, the center ofgravity of the battery module 40 is essentially in the center of thebattery module 40. In general, the clamping device 300 ₁ can be arrangedbetween two adjacent battery cells, by way of example battery cells 100₁, 100 ₂ or battery cells 100 ₃, 100 ₄ of the multiplicity of batterycells 100 ₁ . . . 100 ₄ .

FIG. 5 illustrates a schematic plan view of another battery module 50having a clamping device 300 ₁ in accordance with a further embodimentof the invention.

The battery module 50 is similar to the battery module 20 that isdescribed with regard to FIG. 2, wherein the packaging device isembodied as a housing 200 by way of example in one piece and/or as abath-shaped housing shell.

FIG. 6 illustrates a schematic plan view of a battery module 60 havingtwo clamping devices 300 ₁, 300 ₂ in accordance with the invention afurther embodiment of the invention.

The battery module 60 corresponds essentially to the battery module 20that is described with regard to FIG. 2. Furthermore, the battery module60 comprises a second clamping device 300 ₂ that can be arranged, asillustrated by way of example in FIG. 6, between the second end plate210 ₂ and an adjacent battery cell 100 ₄ of the multiplicity of batterycells 100 ₁ . . . 100 ₄ .

FIGS. 7-15 illustrate schematic lateral sectional views of clampingdevices 300 in accordance with embodiments of the invention.

The clamping device 300 in accordance with FIG. 7 comprises aballoon-type receptacle 320 having an internal space 310 than can befilled. The receptacle 320 comprises a connection 390 that is closedwith a closure or valve 395. The connection 390 can be arranged on aboundary region of the receptacle, as illustrated in FIG. 7. Theballoon-type receptacle 320 can be embodied in one piece, as illustratedin FIG. 7. The balloon-type receptacle 320 can be embodied by way ofexample in a rectangular, such as square, or round shape.

The clamping device 300 in accordance with FIG. 8 comprises acushion-type receptacle that comprises a first foil/film 330 ₁, a secondfoil/film 330 ₂, and a connection 390, which are connected to oneanother by means of seams 380 such as adhesive seams or weld seams sothat an internal space 310 is formed. The connection 390 is closed bymeans of a closure or valve 395. The cushion-type receptacle 320 can beembodied by way of example in a rectangular, such as square, or roundshape.

The clamping device 300 in accordance with FIG. 9 comprises a bag-typereceptacle that comprises a first foil/film 330 ₁, a second foil/film330 ₂, and a connection 390, which are connected to one another by meansof seams 380 such as adhesive seams or weld seams so that an internalspace 310 is formed. The first foil/film 330 ₁ and the second foil/film330 ₂ can comprise folds so that the receptacle can be embodied in theform of a folded bellows or a concertina. The connection 390 is closedby means of a closure or valve 395. The bag-type receptacle can beembodied by way of example in a rectangular, such as square, or roundshape.

The clamping device 300 in accordance with FIG. 10 comprises areceptacle that comprises an element (carrying element, carrier) 340 anda foil/film 330, which are connected to one another by means of seams380 such as adhesive seams or weld seams so that an internal space 310is formed. The element 340 is dimensionally stable and supports thefoil/film 330. The element 340 can be embodied by way of example as anend plate, housing, frame element, carrier frame or crash frame. Theconnection 390 is embodied in a boundary region of the element 340 andis closed by means of a closure or valve 395. The connection 390 isconnected in a fluid conductive manner in the same boundary region tothe internal space 310 so that an additional internal space having aconstant volume (dead volume or dead space) in the element 340 inrelation to the internal space 310 having a variable volume andconsequently its influence during a pressure change is comparativelysmall. Consequently the relationship of the volume of the internal space310 to the volume of the additional internal space determines an elasticconstant of the clamping device 300. The receptacle can be embodied byway of example in a rectangular, such as square, or round shape.

The clamping device 300 in accordance with FIG. 11 correspondsessentially to the clamping device 300 illustrated in FIG. 10. Theconnection 390 is connected in a central region in a fluid conductivemanner to the internal space 310 having a variable volume so that theadditional internal space having a constant volume in the element 340 inrelation to the internal space 310 having a variable volume andconsequently its influence during a pressure change is greater incomparison to the clamping device 300 that is illustrated in FIG. 10.

The clamping device 300 in accordance with FIG. 12 correspondsessentially to the clamping device 300 that is illustrated in FIG. 10.The element 340 comprises a further additional internal space 310 ₃having a constant volume that is connected in a fluid conductive mannerto the connection 390 and the internal space 310 ₁ so that theadditional internal space having a constant volume in the element 340 inrelation to the internal space 310 ₁ having a variable volume andconsequently its influence in the case of a change in pressure isessentially greater in comparison to the clamping device 300 that isillustrated in FIG. 10. It is possible by means of selecting a largedead volume to achieve a reduction in pressure as the gas is escaping.

The clamping device 300 in accordance with FIG. 13 correspondsessentially to a combination of the clamping device 300 that isillustrated in FIG. 10 and the clamping device 300 that is illustratedin FIG. 12. The element 340 comprises the further additional internalspace 310 ₃ having a constant volume, and the connection 390 isconnected in the central region in a fluid conductive manner to theadditional internal space 310 ₃ so that the additional internal spacehaving a constant volume in the element 340 in relation to the internalspace 310 ₁ having a variable volume, and consequently its influence inthe case of a change in pressure is even greater in comparison to theclamping device 300 that is illustrated in FIG. 10.

The clamping device 300 in accordance with FIG. 14 correspondsessentially to the clamping device 300 that is illustrated in FIG. 12.The connection 390 is connected in a fluid conductive manner at aperipheral surface of the further additional internal space 310 ₃ to thefurther additional internal space 310 ₃ so that the clamping device 300can be embodied in a more compact manner in comparison to the clampingdevice 300 that is illustrated in FIG. 12.

The clamping device 300 in accordance with FIG. 15 is similar to theclamping device 300 that is illustrated in FIG. 14. The clamping device300 in accordance with FIG. 14 comprises a receptacle that comprises anelement 340, a first foil/film 330 ₁ and a second foil/film 330 ₂ thatare arranged opposite one another and/or are connected to the element340 by means of seams 380 such as an adhesive seam or weld seams so thata first internal space 310 ₁ having a first variable volume, a secondinternal space 310 ₂ having a variable volume and a third internal space310 ₃ having a constant volume that are connected in a fluid conductivemanner to one another are formed. The element 340 can be described as“communicating ducts”. Whereas the first foil/film 330 ₁ is used forclamping a first battery cell or a multiplicity of battery cells 100 ₃,100 ₄, the second foil/film 330 ₂ can be used by way of example, asdescribed with regard to FIG. 4, for clamping a second battery cell or amultiplicity of battery cells 100 ₁, 100 ₂. Alternatively, the secondfoil/film 330 ₂ can be used as a compensating element. In so doing, therelationship of the volume of the first internal space 310 ₁ withrespect to the total volume of the second internal space 330 ₂ and thethird internal space 330 ₃ determines the elastic constants of thisclamping device 300.

FIGS. 16-18 illustrate schematic longitudinal sectional views ofclamping devices 300 in accordance with other embodiments of theinvention.

The clamping device 300 in accordance with FIG. 16 correspondsessentially to the clamping device 300 that is illustrated in FIG. 8 andcomprises the cushion-type receptacle. The foils/films 330 and theconnection 390 are connected to one another in a boundary region bymeans of seams such as adhesive seams 380 or weld seams so that theinternal space 310 is formed.

The clamping device 300 in accordance with FIG. 17 correspondsessentially to the clamping device 300 that is illustrated in FIG. 16.The clamping device 300 comprises furthermore a multiplicity of linearseams 385 such as adhesive seams or weld seams that connect thefoils/films 330 to one another and are embodied in the internal space310 in such a manner that the internal space 310 is structured orsubdivided into a multiplicity of chambers that are connected to oneanother in a fluid conductive manner.

The clamping device 300 in accordance with FIG. 18 correspondsessentially to the clamping device 300 that is illustrated in FIG. 17.The clamping device 300 comprises furthermore a multiplicity ofcross-shaped seams 385 such as adhesive seams or weld seams that connectthe foils/films 330 to one another and are embodied in the internalspace 310 in such a manner that the internal space 310 is structured orsubdivided into a multiplicity of chambers that are connected to oneanother in a fluid conductive manner.

Alternatively, a clamping device can comprise a multiplicity of internalchambers or a multiplicity of chambers that are not connected to oneanother in a fluid conductive manner.

FIG. 19 illustrates a schematic sectional view of a clamping system 70in accordance with another embodiment of the invention.

The clamping system 70 comprises a clamping element 300 ₂′ having a deadvolume 310 ₃, which is similar to the clamping device 300 that isdescribed with regard to FIG. 13, an element 300 ₁′, which is similar tothe clamping device 300 that is described with regard to FIG. 11, achamber 365 for receiving a fluid volume and connecting ducts 355, whichconnect the clamping element 300 ₂′, the element 300 ₁′, the connection390 and the chamber 365 to one another in a fluid conductive manner. Thefoil/film 330 ₁ of the element 300 ₁′ can be recessed, as illustrated inFIG. 19. The element 300 ₁′ can be used as a clamping element forclamping battery cells or as an expansion element for storing a variablefluid volume without changing the external dimensions. The clampingsystem 70 can comprise a liquid as a working medium and, in the chamber365, a gas as a pressure storage medium.

The system 70 can comprise a multiplicity of clamping elements and/or beinstalled by way of example in a crash frame.

FIG. 20 illustrates a schematic sectional view of a modified clampingsystem 80 in accordance with this embodiment of the invention.

The modified clamping system 80 corresponds essentially to the clampingsystem 70 that is described with regard to FIG. 19. In contrast to theclamping system 70, the modified clamping system 80 comprises separatecarrying elements 350 ₁, 350 ₂, a separate storage element 360 in whichthe chamber 365 is embodied, and/or separate communicating connectionelements (ducts, hoses) 350 ₃ so that a free, where necessary spatiallyseparate, arrangement of the elements is rendered possible.

In conclusion, it is to be noted that expressions such as “including”,“containing” and “comprising” or the like do not exclude that furtherelements or steps can be provided. The numbers used are merely anexample so that a multiplicity can include 2, 4, 5, 6 or more elementsor steps. Furthermore, reference is made to the fact that “a” or “one”do not exclude a multiplicity. Furthermore, it is to be noted thatnumbers in words or ordinal numbers such as “first”, “second” etc. areused exclusively to differentiate between elements and steps withoutspecifying or limiting a chronological order of the arrangement of theelements or of the performance of the steps. Moreover, the features thatare described in conjunction with the different embodiments can becombined in an arbitrary manner with one another. Finally, it is to benoted that the reference numerals in the claims are not be regarded aslimiting the protective scope of the claims.

1. A clamping device (300) for battery cells (100), comprising: areceptacle that comprises a space (310) having a variable volume forreceiving a fluid, wherein: the receptacle is configured so that abattery cell (100) or a multiplicity of battery cells (100) can beclamped.
 2. The clamping device (300) as claimed in claim 1, wherein:the receptacle comprises a membrane (320) or a flexible membrane, andthe membrane (320) is embodied in a balloon-type, bag-type, cushion-typeor drum-type manner.
 3. The clamping device (300) as claimed in claim 1,wherein: the receptacle comprises a membrane (320) or a flexiblemembrane and an element (340) for carrying the membrane (320).
 4. Theclamping device (300) as claimed in claim 1, wherein; the receptaclecontains the fluid, or the fluid comprises a liquid, water, siliconeoil, gas, inert gas, nitrogen, noble gas, argon, krypton or gel, thefluid is compressible, or the fluid is non-compressible.
 5. A batterymodule (20; 30; 40; 50; 60), comprising: the clamping device (300) asclaimed in claim
 1. 6. A battery, comprising: the clamping device (300)as claimed in claim
 1. 7. A battery system, comprising: the clampingdevice (300) as claimed in claim
 1. 8. A vehicle, comprising: theclamping device (300) as claimed in claim
 1. 9. A method for producing abattery module (20; 30; 40; 50; 60), comprising: providing a clampingdevice (300) comprising a receptacle that comprises a space (310) havinga variable volume for receiving a fluid, wherein the receptacle isembodied in such a manner that a battery cell (100) or a multiplicity ofbattery cells (100) can be clamped, arranging the clamping device (300)and the battery cell (100) or the multiplicity of battery cells (100) inthe battery module (20; 30; 40; 50; 60), and clamping the clampingdevice (300) for clamping the battery cell (100) of the multiplicity ofbattery cells (100).
 10. The method as claimed in claim 9, wherein: theprocedure of clamping the clamping device (300) includes: filling thespace (310) with the fluid, or closing the receptacle.
 11. The method asclaimed in claim 9, furthermore comprising: filling the space (310) withthe fluid, closing the receptacle, and cooling or liquefying the fluid,wherein: the procedure of clamping the clamping device (300) includes:warming the fluid in the receptacle or allowing the re-warming of thefluid in the receptacle.
 12. The method as claimed in claim 9,furthermore comprising: checking a pressure of the fluid in thereceptacle, or adjusting the pressure.
 13. The clamping device (300) asclaimed in claim 1, wherein the receptacle comprises a membrane (320)embodied in an elastic or flexible manner.
 14. The clamping device (300)as claimed in claim 1, wherein the receptacle comprises a membrane(320), and the membrane (320) comprises a foil/film (330), a syntheticmaterial film, a metallized film or a metal foil or fabric.
 15. Theclamping device (300) as claimed in claim 1, wherein the receptaclecomprises a membrane (320) or a flexible membrane, and the membrane(320) is embodied in an electrically conductive manner.
 16. The clampingdevice (300) as claimed in claim 1, wherein the receptacle comprises amembrane (320) or a flexible membrane, and the membrane comprises anelectrically conductive material, aluminum, copper or carbon.
 17. Theclamping device (300) as claimed in claim 1, wherein the receptaclecomprises a membrane (320) or a flexible membrane, and the membrane(320) is embodied in an electrically non-conductive manner.
 18. Theclamping device (300) as claimed in claim 3, wherein the element (340)comprises a metal, aluminum or a synthetic material.
 19. The clampingdevice (300) as claimed in claim 3, wherein the element (340) is an endplate (210′).
 20. The clamping device (300) as claimed in claim 1,wherein the receptacle comprises a closure (395), a valve, a safetyvalve or an excess pressure valve.
 21. The clamping device (300) asclaimed in claim 1, wherein the receptacle comprises a seam, adhesiveseam or weld seam.